"We have a great storyline this year: They lose the house," executive producer Chuck Lorre tells THR. "They stay at a motel for a while. They stay with [new series regular] Mimi Kennedy's Marjorie and the cats for a while. It's a struggle. Christy is trying to keep her family afloat and keep her daughter afloat after the adoption. Her daughter is not doing well emotionally. It's hard. And she's also trying to help Jamie Pressly's character, who is trying to get sober. She's a woman with a lot of money and not much else going on."

Lorre also confirmed that Kevin Pollak would return to reprise his role as Alvin, the boyfriend who abandoned Bonnie (Allison Janney) while she was in the hospital giving birth to Christy.

Said Lorre of the joys of working on Mom: "I love the challenge of trying to find stories that explore what happens in life versus what happens in television. I love what the other shows do, but Mom is an opportunity to do something else. I really haven't had that opportunity since Grace Under Fire,and that was 21 years ago. It's a great opportunity to write stuff that maybe touches on some real serious stuff and hopefully find a way to somehow make it funny as well. Having the first year under our belt gave us a little more confidence."

Pressly is repped by CAA, Mosaic and Bloom Hergott.

Mom returns for its second season on Monday, Sept. 29 at 8:30 p.m. on CBS.